4 * Copyright (C) International Business Machines Corp., 2002,2008
5 * Author(s): Steve French (sfrench@us.ibm.com)
6 * Jeremy Allison (jra@samba.org) 2006.
8 * This library is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU Lesser General Public License as published
10 * by the Free Software Foundation; either version 2.1 of the License, or
11 * (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
16 * the GNU Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public License
19 * along with this library; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 #include <linux/list.h>
25 #include <linux/gfp.h>
26 #include <linux/wait.h>
27 #include <linux/net.h>
28 #include <linux/delay.h>
29 #include <linux/freezer.h>
30 #include <linux/tcp.h>
31 #include <linux/bvec.h>
32 #include <linux/highmem.h>
33 #include <linux/uaccess.h>
34 #include <asm/processor.h>
35 #include <linux/mempool.h>
36 #include <linux/sched/signal.h>
39 #include "cifsproto.h"
40 #include "cifs_debug.h"
41 #include "smb2proto.h"
42 #include "smbdirect.h"
44 /* Max number of iovectors we can use off the stack when sending requests. */
45 #define CIFS_MAX_IOV_SIZE 8
48 cifs_wake_up_task(struct mid_q_entry *mid)
50 wake_up_process(mid->callback_data);
54 AllocMidQEntry(const struct smb_hdr *smb_buffer, struct TCP_Server_Info *server)
56 struct mid_q_entry *temp;
59 cifs_dbg(VFS, "Null TCP session in AllocMidQEntry\n");
63 temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
64 memset(temp, 0, sizeof(struct mid_q_entry));
65 kref_init(&temp->refcount);
66 temp->mid = get_mid(smb_buffer);
67 temp->pid = current->pid;
68 temp->command = cpu_to_le16(smb_buffer->Command);
69 cifs_dbg(FYI, "For smb_command %d\n", smb_buffer->Command);
70 /* do_gettimeofday(&temp->when_sent);*/ /* easier to use jiffies */
71 /* when mid allocated can be before when sent */
72 temp->when_alloc = jiffies;
73 temp->server = server;
76 * The default is for the mid to be synchronous, so the
77 * default callback just wakes up the current task.
79 temp->callback = cifs_wake_up_task;
80 temp->callback_data = current;
82 atomic_inc(&midCount);
83 temp->mid_state = MID_REQUEST_ALLOCATED;
87 static void _cifs_mid_q_entry_release(struct kref *refcount)
89 struct mid_q_entry *midEntry =
90 container_of(refcount, struct mid_q_entry, refcount);
91 #ifdef CONFIG_CIFS_STATS2
92 __le16 command = midEntry->server->vals->lock_cmd;
93 __u16 smb_cmd = le16_to_cpu(midEntry->command);
95 unsigned long roundtrip_time;
97 struct TCP_Server_Info *server = midEntry->server;
99 if (midEntry->resp_buf && (midEntry->mid_flags & MID_WAIT_CANCELLED) &&
100 midEntry->mid_state == MID_RESPONSE_RECEIVED &&
101 server->ops->handle_cancelled_mid)
102 server->ops->handle_cancelled_mid(midEntry->resp_buf, server);
104 midEntry->mid_state = MID_FREE;
105 atomic_dec(&midCount);
106 if (midEntry->large_buf)
107 cifs_buf_release(midEntry->resp_buf);
109 cifs_small_buf_release(midEntry->resp_buf);
110 #ifdef CONFIG_CIFS_STATS2
112 if (now < midEntry->when_alloc)
113 cifs_server_dbg(VFS, "invalid mid allocation time\n");
114 roundtrip_time = now - midEntry->when_alloc;
116 if (smb_cmd < NUMBER_OF_SMB2_COMMANDS) {
117 if (atomic_read(&server->num_cmds[smb_cmd]) == 0) {
118 server->slowest_cmd[smb_cmd] = roundtrip_time;
119 server->fastest_cmd[smb_cmd] = roundtrip_time;
121 if (server->slowest_cmd[smb_cmd] < roundtrip_time)
122 server->slowest_cmd[smb_cmd] = roundtrip_time;
123 else if (server->fastest_cmd[smb_cmd] > roundtrip_time)
124 server->fastest_cmd[smb_cmd] = roundtrip_time;
126 cifs_stats_inc(&server->num_cmds[smb_cmd]);
127 server->time_per_cmd[smb_cmd] += roundtrip_time;
130 * commands taking longer than one second (default) can be indications
131 * that something is wrong, unless it is quite a slow link or a very
132 * busy server. Note that this calc is unlikely or impossible to wrap
133 * as long as slow_rsp_threshold is not set way above recommended max
134 * value (32767 ie 9 hours) and is generally harmless even if wrong
135 * since only affects debug counters - so leaving the calc as simple
136 * comparison rather than doing multiple conversions and overflow
139 if ((slow_rsp_threshold != 0) &&
140 time_after(now, midEntry->when_alloc + (slow_rsp_threshold * HZ)) &&
141 (midEntry->command != command)) {
143 * smb2slowcmd[NUMBER_OF_SMB2_COMMANDS] counts by command
144 * NB: le16_to_cpu returns unsigned so can not be negative below
146 if (smb_cmd < NUMBER_OF_SMB2_COMMANDS)
147 cifs_stats_inc(&server->smb2slowcmd[smb_cmd]);
149 trace_smb3_slow_rsp(smb_cmd, midEntry->mid, midEntry->pid,
150 midEntry->when_sent, midEntry->when_received);
151 if (cifsFYI & CIFS_TIMER) {
152 pr_debug(" CIFS slow rsp: cmd %d mid %llu",
153 midEntry->command, midEntry->mid);
154 cifs_info(" A: 0x%lx S: 0x%lx R: 0x%lx\n",
155 now - midEntry->when_alloc,
156 now - midEntry->when_sent,
157 now - midEntry->when_received);
162 mempool_free(midEntry, cifs_mid_poolp);
165 void cifs_mid_q_entry_release(struct mid_q_entry *midEntry)
167 spin_lock(&GlobalMid_Lock);
168 kref_put(&midEntry->refcount, _cifs_mid_q_entry_release);
169 spin_unlock(&GlobalMid_Lock);
172 void DeleteMidQEntry(struct mid_q_entry *midEntry)
174 cifs_mid_q_entry_release(midEntry);
178 cifs_delete_mid(struct mid_q_entry *mid)
180 spin_lock(&GlobalMid_Lock);
181 if (!(mid->mid_flags & MID_DELETED)) {
182 list_del_init(&mid->qhead);
183 mid->mid_flags |= MID_DELETED;
185 spin_unlock(&GlobalMid_Lock);
187 DeleteMidQEntry(mid);
191 * smb_send_kvec - send an array of kvecs to the server
192 * @server: Server to send the data to
193 * @smb_msg: Message to send
194 * @sent: amount of data sent on socket is stored here
196 * Our basic "send data to server" function. Should be called with srv_mutex
197 * held. The caller is responsible for handling the results.
200 smb_send_kvec(struct TCP_Server_Info *server, struct msghdr *smb_msg,
205 struct socket *ssocket = server->ssocket;
209 smb_msg->msg_name = (struct sockaddr *) &server->dstaddr;
210 smb_msg->msg_namelen = sizeof(struct sockaddr);
211 smb_msg->msg_control = NULL;
212 smb_msg->msg_controllen = 0;
213 if (server->noblocksnd)
214 smb_msg->msg_flags = MSG_DONTWAIT + MSG_NOSIGNAL;
216 smb_msg->msg_flags = MSG_NOSIGNAL;
218 while (msg_data_left(smb_msg)) {
220 * If blocking send, we try 3 times, since each can block
221 * for 5 seconds. For nonblocking we have to try more
222 * but wait increasing amounts of time allowing time for
223 * socket to clear. The overall time we wait in either
224 * case to send on the socket is about 15 seconds.
225 * Similarly we wait for 15 seconds for a response from
226 * the server in SendReceive[2] for the server to send
227 * a response back for most types of requests (except
228 * SMB Write past end of file which can be slow, and
229 * blocking lock operations). NFS waits slightly longer
230 * than CIFS, but this can make it take longer for
231 * nonresponsive servers to be detected and 15 seconds
232 * is more than enough time for modern networks to
233 * send a packet. In most cases if we fail to send
234 * after the retries we will kill the socket and
235 * reconnect which may clear the network problem.
237 rc = sock_sendmsg(ssocket, smb_msg);
241 (!server->noblocksnd && (retries > 2))) {
242 cifs_server_dbg(VFS, "sends on sock %p stuck for 15 seconds\n",
246 msleep(1 << retries);
254 /* should never happen, letting socket clear before
255 retrying is our only obvious option here */
256 cifs_server_dbg(VFS, "tcp sent no data\n");
261 /* send was at least partially successful */
263 retries = 0; /* in case we get ENOSPC on the next send */
269 smb_rqst_len(struct TCP_Server_Info *server, struct smb_rqst *rqst)
274 unsigned long buflen = 0;
276 if (server->vals->header_preamble_size == 0 &&
277 rqst->rq_nvec >= 2 && rqst->rq_iov[0].iov_len == 4) {
278 iov = &rqst->rq_iov[1];
279 nvec = rqst->rq_nvec - 1;
282 nvec = rqst->rq_nvec;
285 /* total up iov array first */
286 for (i = 0; i < nvec; i++)
287 buflen += iov[i].iov_len;
290 * Add in the page array if there is one. The caller needs to make
291 * sure rq_offset and rq_tailsz are set correctly. If a buffer of
292 * multiple pages ends at page boundary, rq_tailsz needs to be set to
295 if (rqst->rq_npages) {
296 if (rqst->rq_npages == 1)
297 buflen += rqst->rq_tailsz;
300 * If there is more than one page, calculate the
301 * buffer length based on rq_offset and rq_tailsz
303 buflen += rqst->rq_pagesz * (rqst->rq_npages - 1) -
305 buflen += rqst->rq_tailsz;
313 __smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
314 struct smb_rqst *rqst)
319 unsigned int send_length = 0;
321 sigset_t mask, oldmask;
322 size_t total_len = 0, sent, size;
323 struct socket *ssocket = server->ssocket;
324 struct msghdr smb_msg;
326 __be32 rfc1002_marker;
328 if (cifs_rdma_enabled(server)) {
329 /* return -EAGAIN when connecting or reconnecting */
331 if (server->smbd_conn)
332 rc = smbd_send(server, num_rqst, rqst);
339 if (signal_pending(current)) {
340 cifs_dbg(FYI, "signal is pending before sending any data\n");
344 /* cork the socket */
345 kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
346 (char *)&val, sizeof(val));
348 for (j = 0; j < num_rqst; j++)
349 send_length += smb_rqst_len(server, &rqst[j]);
350 rfc1002_marker = cpu_to_be32(send_length);
353 * We should not allow signals to interrupt the network send because
354 * any partial send will cause session reconnects thus increasing
355 * latency of system calls and overload a server with unnecessary
360 sigprocmask(SIG_BLOCK, &mask, &oldmask);
362 /* Generate a rfc1002 marker for SMB2+ */
363 if (server->vals->header_preamble_size == 0) {
365 .iov_base = &rfc1002_marker,
368 iov_iter_kvec(&smb_msg.msg_iter, WRITE, &hiov, 1, 4);
369 rc = smb_send_kvec(server, &smb_msg, &sent);
377 cifs_dbg(FYI, "Sending smb: smb_len=%u\n", send_length);
379 for (j = 0; j < num_rqst; j++) {
380 iov = rqst[j].rq_iov;
381 n_vec = rqst[j].rq_nvec;
384 for (i = 0; i < n_vec; i++) {
385 dump_smb(iov[i].iov_base, iov[i].iov_len);
386 size += iov[i].iov_len;
389 iov_iter_kvec(&smb_msg.msg_iter, WRITE, iov, n_vec, size);
391 rc = smb_send_kvec(server, &smb_msg, &sent);
397 /* now walk the page array and send each page in it */
398 for (i = 0; i < rqst[j].rq_npages; i++) {
401 bvec.bv_page = rqst[j].rq_pages[i];
402 rqst_page_get_length(&rqst[j], i, &bvec.bv_len,
405 iov_iter_bvec(&smb_msg.msg_iter, WRITE,
406 &bvec, 1, bvec.bv_len);
407 rc = smb_send_kvec(server, &smb_msg, &sent);
416 sigprocmask(SIG_SETMASK, &oldmask, NULL);
419 * If signal is pending but we have already sent the whole packet to
420 * the server we need to return success status to allow a corresponding
421 * mid entry to be kept in the pending requests queue thus allowing
422 * to handle responses from the server by the client.
424 * If only part of the packet has been sent there is no need to hide
425 * interrupt because the session will be reconnected anyway, so there
426 * won't be any response from the server to handle.
429 if (signal_pending(current) && (total_len != send_length)) {
430 cifs_dbg(FYI, "signal is pending after attempt to send\n");
436 kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
437 (char *)&val, sizeof(val));
439 if ((total_len > 0) && (total_len != send_length)) {
440 cifs_dbg(FYI, "partial send (wanted=%u sent=%zu): terminating session\n",
441 send_length, total_len);
443 * If we have only sent part of an SMB then the next SMB could
444 * be taken as the remainder of this one. We need to kill the
445 * socket so the server throws away the partial SMB
447 server->tcpStatus = CifsNeedReconnect;
448 trace_smb3_partial_send_reconnect(server->CurrentMid,
452 if (rc < 0 && rc != -EINTR)
453 cifs_server_dbg(VFS, "Error %d sending data on socket to server\n",
462 smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
463 struct smb_rqst *rqst, int flags)
466 struct smb2_transform_hdr tr_hdr;
467 struct smb_rqst cur_rqst[MAX_COMPOUND];
470 if (!(flags & CIFS_TRANSFORM_REQ))
471 return __smb_send_rqst(server, num_rqst, rqst);
473 if (num_rqst > MAX_COMPOUND - 1)
476 memset(&cur_rqst[0], 0, sizeof(cur_rqst));
477 memset(&iov, 0, sizeof(iov));
478 memset(&tr_hdr, 0, sizeof(tr_hdr));
480 iov.iov_base = &tr_hdr;
481 iov.iov_len = sizeof(tr_hdr);
482 cur_rqst[0].rq_iov = &iov;
483 cur_rqst[0].rq_nvec = 1;
485 if (!server->ops->init_transform_rq) {
486 cifs_server_dbg(VFS, "Encryption requested but transform "
487 "callback is missing\n");
491 rc = server->ops->init_transform_rq(server, num_rqst + 1,
496 rc = __smb_send_rqst(server, num_rqst + 1, &cur_rqst[0]);
497 smb3_free_compound_rqst(num_rqst, &cur_rqst[1]);
502 smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer,
503 unsigned int smb_buf_length)
506 struct smb_rqst rqst = { .rq_iov = iov,
509 iov[0].iov_base = smb_buffer;
511 iov[1].iov_base = (char *)smb_buffer + 4;
512 iov[1].iov_len = smb_buf_length;
514 return __smb_send_rqst(server, 1, &rqst);
518 wait_for_free_credits(struct TCP_Server_Info *server, const int num_credits,
519 const int timeout, const int flags,
520 unsigned int *instance)
528 t = MAX_JIFFY_OFFSET;
530 t = msecs_to_jiffies(timeout);
532 optype = flags & CIFS_OP_MASK;
536 credits = server->ops->get_credits_field(server, optype);
537 /* Since an echo is already inflight, no need to wait to send another */
538 if (*credits <= 0 && optype == CIFS_ECHO_OP)
541 spin_lock(&server->req_lock);
542 if ((flags & CIFS_TIMEOUT_MASK) == CIFS_NON_BLOCKING) {
543 /* oplock breaks must not be held up */
545 if (server->in_flight > server->max_in_flight)
546 server->max_in_flight = server->in_flight;
548 *instance = server->reconnect_instance;
549 spin_unlock(&server->req_lock);
554 if (*credits < num_credits) {
555 spin_unlock(&server->req_lock);
556 cifs_num_waiters_inc(server);
557 rc = wait_event_killable_timeout(server->request_q,
558 has_credits(server, credits, num_credits), t);
559 cifs_num_waiters_dec(server);
561 trace_smb3_credit_timeout(server->CurrentMid,
562 server->hostname, num_credits);
563 cifs_server_dbg(VFS, "wait timed out after %d ms\n",
567 if (rc == -ERESTARTSYS)
569 spin_lock(&server->req_lock);
571 if (server->tcpStatus == CifsExiting) {
572 spin_unlock(&server->req_lock);
577 * For normal commands, reserve the last MAX_COMPOUND
578 * credits to compound requests.
579 * Otherwise these compounds could be permanently
580 * starved for credits by single-credit requests.
582 * To prevent spinning CPU, block this thread until
583 * there are >MAX_COMPOUND credits available.
584 * But only do this is we already have a lot of
585 * credits in flight to avoid triggering this check
586 * for servers that are slow to hand out credits on
589 if (!optype && num_credits == 1 &&
590 server->in_flight > 2 * MAX_COMPOUND &&
591 *credits <= MAX_COMPOUND) {
592 spin_unlock(&server->req_lock);
593 cifs_num_waiters_inc(server);
594 rc = wait_event_killable_timeout(
596 has_credits(server, credits,
599 cifs_num_waiters_dec(server);
601 trace_smb3_credit_timeout(
603 server->hostname, num_credits);
604 cifs_server_dbg(VFS, "wait timed out after %d ms\n",
608 if (rc == -ERESTARTSYS)
610 spin_lock(&server->req_lock);
615 * Can not count locking commands against total
616 * as they are allowed to block on server.
619 /* update # of requests on the wire to server */
620 if ((flags & CIFS_TIMEOUT_MASK) != CIFS_BLOCKING_OP) {
621 *credits -= num_credits;
622 server->in_flight += num_credits;
623 if (server->in_flight > server->max_in_flight)
624 server->max_in_flight = server->in_flight;
625 *instance = server->reconnect_instance;
627 spin_unlock(&server->req_lock);
635 wait_for_free_request(struct TCP_Server_Info *server, const int flags,
636 unsigned int *instance)
638 return wait_for_free_credits(server, 1, -1, flags,
643 wait_for_compound_request(struct TCP_Server_Info *server, int num,
644 const int flags, unsigned int *instance)
648 credits = server->ops->get_credits_field(server, flags & CIFS_OP_MASK);
650 spin_lock(&server->req_lock);
651 if (*credits < num) {
653 * Return immediately if not too many requests in flight since
654 * we will likely be stuck on waiting for credits.
656 if (server->in_flight < num - *credits) {
657 spin_unlock(&server->req_lock);
661 spin_unlock(&server->req_lock);
663 return wait_for_free_credits(server, num, 60000, flags,
668 cifs_wait_mtu_credits(struct TCP_Server_Info *server, unsigned int size,
669 unsigned int *num, struct cifs_credits *credits)
673 credits->instance = server->reconnect_instance;
677 static int allocate_mid(struct cifs_ses *ses, struct smb_hdr *in_buf,
678 struct mid_q_entry **ppmidQ)
680 if (ses->server->tcpStatus == CifsExiting) {
684 if (ses->server->tcpStatus == CifsNeedReconnect) {
685 cifs_dbg(FYI, "tcp session dead - return to caller to retry\n");
689 if (ses->status == CifsNew) {
690 if ((in_buf->Command != SMB_COM_SESSION_SETUP_ANDX) &&
691 (in_buf->Command != SMB_COM_NEGOTIATE))
693 /* else ok - we are setting up session */
696 if (ses->status == CifsExiting) {
697 /* check if SMB session is bad because we are setting it up */
698 if (in_buf->Command != SMB_COM_LOGOFF_ANDX)
700 /* else ok - we are shutting down session */
703 *ppmidQ = AllocMidQEntry(in_buf, ses->server);
706 spin_lock(&GlobalMid_Lock);
707 list_add_tail(&(*ppmidQ)->qhead, &ses->server->pending_mid_q);
708 spin_unlock(&GlobalMid_Lock);
713 wait_for_response(struct TCP_Server_Info *server, struct mid_q_entry *midQ)
717 error = wait_event_freezekillable_unsafe(server->response_q,
718 midQ->mid_state != MID_REQUEST_SUBMITTED);
726 cifs_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst)
729 struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
730 struct mid_q_entry *mid;
732 if (rqst->rq_iov[0].iov_len != 4 ||
733 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
734 return ERR_PTR(-EIO);
736 /* enable signing if server requires it */
738 hdr->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
740 mid = AllocMidQEntry(hdr, server);
742 return ERR_PTR(-ENOMEM);
744 rc = cifs_sign_rqst(rqst, server, &mid->sequence_number);
746 DeleteMidQEntry(mid);
754 * Send a SMB request and set the callback function in the mid to handle
755 * the result. Caller is responsible for dealing with timeouts.
758 cifs_call_async(struct TCP_Server_Info *server, struct smb_rqst *rqst,
759 mid_receive_t *receive, mid_callback_t *callback,
760 mid_handle_t *handle, void *cbdata, const int flags,
761 const struct cifs_credits *exist_credits)
764 struct mid_q_entry *mid;
765 struct cifs_credits credits = { .value = 0, .instance = 0 };
766 unsigned int instance;
769 optype = flags & CIFS_OP_MASK;
771 if ((flags & CIFS_HAS_CREDITS) == 0) {
772 rc = wait_for_free_request(server, flags, &instance);
776 credits.instance = instance;
778 instance = exist_credits->instance;
780 mutex_lock(&server->srv_mutex);
783 * We can't use credits obtained from the previous session to send this
784 * request. Check if there were reconnects after we obtained credits and
785 * return -EAGAIN in such cases to let callers handle it.
787 if (instance != server->reconnect_instance) {
788 mutex_unlock(&server->srv_mutex);
789 add_credits_and_wake_if(server, &credits, optype);
793 mid = server->ops->setup_async_request(server, rqst);
795 mutex_unlock(&server->srv_mutex);
796 add_credits_and_wake_if(server, &credits, optype);
800 mid->receive = receive;
801 mid->callback = callback;
802 mid->callback_data = cbdata;
803 mid->handle = handle;
804 mid->mid_state = MID_REQUEST_SUBMITTED;
806 /* put it on the pending_mid_q */
807 spin_lock(&GlobalMid_Lock);
808 list_add_tail(&mid->qhead, &server->pending_mid_q);
809 spin_unlock(&GlobalMid_Lock);
812 * Need to store the time in mid before calling I/O. For call_async,
813 * I/O response may come back and free the mid entry on another thread.
815 cifs_save_when_sent(mid);
816 cifs_in_send_inc(server);
817 rc = smb_send_rqst(server, 1, rqst, flags);
818 cifs_in_send_dec(server);
821 revert_current_mid(server, mid->credits);
822 server->sequence_number -= 2;
823 cifs_delete_mid(mid);
826 mutex_unlock(&server->srv_mutex);
831 add_credits_and_wake_if(server, &credits, optype);
837 * Send an SMB Request. No response info (other than return code)
838 * needs to be parsed.
840 * flags indicate the type of request buffer and how long to wait
841 * and whether to log NT STATUS code (error) before mapping it to POSIX error
845 SendReceiveNoRsp(const unsigned int xid, struct cifs_ses *ses,
846 char *in_buf, int flags)
853 iov[0].iov_base = in_buf;
854 iov[0].iov_len = get_rfc1002_length(in_buf) + 4;
855 flags |= CIFS_NO_RSP_BUF;
856 rc = SendReceive2(xid, ses, iov, 1, &resp_buf_type, flags, &rsp_iov);
857 cifs_dbg(NOISY, "SendRcvNoRsp flags %d rc %d\n", flags, rc);
863 cifs_sync_mid_result(struct mid_q_entry *mid, struct TCP_Server_Info *server)
867 cifs_dbg(FYI, "%s: cmd=%d mid=%llu state=%d\n",
868 __func__, le16_to_cpu(mid->command), mid->mid, mid->mid_state);
870 spin_lock(&GlobalMid_Lock);
871 switch (mid->mid_state) {
872 case MID_RESPONSE_RECEIVED:
873 spin_unlock(&GlobalMid_Lock);
875 case MID_RETRY_NEEDED:
878 case MID_RESPONSE_MALFORMED:
885 if (!(mid->mid_flags & MID_DELETED)) {
886 list_del_init(&mid->qhead);
887 mid->mid_flags |= MID_DELETED;
889 cifs_server_dbg(VFS, "%s: invalid mid state mid=%llu state=%d\n",
890 __func__, mid->mid, mid->mid_state);
893 spin_unlock(&GlobalMid_Lock);
895 DeleteMidQEntry(mid);
900 send_cancel(struct TCP_Server_Info *server, struct smb_rqst *rqst,
901 struct mid_q_entry *mid)
903 return server->ops->send_cancel ?
904 server->ops->send_cancel(server, rqst, mid) : 0;
908 cifs_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
911 unsigned int len = get_rfc1002_length(mid->resp_buf) + 4;
913 dump_smb(mid->resp_buf, min_t(u32, 92, len));
915 /* convert the length into a more usable form */
919 struct smb_rqst rqst = { .rq_iov = iov,
922 iov[0].iov_base = mid->resp_buf;
924 iov[1].iov_base = (char *)mid->resp_buf + 4;
925 iov[1].iov_len = len - 4;
926 /* FIXME: add code to kill session */
927 rc = cifs_verify_signature(&rqst, server,
928 mid->sequence_number);
930 cifs_server_dbg(VFS, "SMB signature verification returned error = %d\n",
934 /* BB special case reconnect tid and uid here? */
935 return map_smb_to_linux_error(mid->resp_buf, log_error);
939 cifs_setup_request(struct cifs_ses *ses, struct TCP_Server_Info *ignored,
940 struct smb_rqst *rqst)
943 struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
944 struct mid_q_entry *mid;
946 if (rqst->rq_iov[0].iov_len != 4 ||
947 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
948 return ERR_PTR(-EIO);
950 rc = allocate_mid(ses, hdr, &mid);
953 rc = cifs_sign_rqst(rqst, ses->server, &mid->sequence_number);
955 cifs_delete_mid(mid);
962 cifs_compound_callback(struct mid_q_entry *mid)
964 struct TCP_Server_Info *server = mid->server;
965 struct cifs_credits credits;
967 credits.value = server->ops->get_credits(mid);
968 credits.instance = server->reconnect_instance;
970 add_credits(server, &credits, mid->optype);
974 cifs_compound_last_callback(struct mid_q_entry *mid)
976 cifs_compound_callback(mid);
977 cifs_wake_up_task(mid);
981 cifs_cancelled_callback(struct mid_q_entry *mid)
983 cifs_compound_callback(mid);
984 DeleteMidQEntry(mid);
988 compound_send_recv(const unsigned int xid, struct cifs_ses *ses,
989 const int flags, const int num_rqst, struct smb_rqst *rqst,
990 int *resp_buf_type, struct kvec *resp_iov)
992 int i, j, optype, rc = 0;
993 struct mid_q_entry *midQ[MAX_COMPOUND];
994 bool cancelled_mid[MAX_COMPOUND] = {false};
995 struct cifs_credits credits[MAX_COMPOUND] = {
996 { .value = 0, .instance = 0 }
998 unsigned int instance;
1000 struct TCP_Server_Info *server;
1002 optype = flags & CIFS_OP_MASK;
1004 for (i = 0; i < num_rqst; i++)
1005 resp_buf_type[i] = CIFS_NO_BUFFER; /* no response buf yet */
1007 if ((ses == NULL) || (ses->server == NULL)) {
1008 cifs_dbg(VFS, "Null session\n");
1012 if (!ses->binding) {
1015 if (ses->chan_count > 1) {
1016 index = (uint)atomic_inc_return(&ses->chan_seq);
1017 index %= ses->chan_count;
1019 server = ses->chans[index].server;
1021 server = cifs_ses_server(ses);
1024 if (server->tcpStatus == CifsExiting)
1028 * Wait for all the requests to become available.
1029 * This approach still leaves the possibility to be stuck waiting for
1030 * credits if the server doesn't grant credits to the outstanding
1031 * requests and if the client is completely idle, not generating any
1033 * This can be handled by the eventual session reconnect.
1035 rc = wait_for_compound_request(server, num_rqst, flags,
1040 for (i = 0; i < num_rqst; i++) {
1041 credits[i].value = 1;
1042 credits[i].instance = instance;
1046 * Make sure that we sign in the same order that we send on this socket
1047 * and avoid races inside tcp sendmsg code that could cause corruption
1051 mutex_lock(&server->srv_mutex);
1054 * All the parts of the compound chain belong obtained credits from the
1055 * same session. We can not use credits obtained from the previous
1056 * session to send this request. Check if there were reconnects after
1057 * we obtained credits and return -EAGAIN in such cases to let callers
1060 if (instance != server->reconnect_instance) {
1061 mutex_unlock(&server->srv_mutex);
1062 for (j = 0; j < num_rqst; j++)
1063 add_credits(server, &credits[j], optype);
1067 for (i = 0; i < num_rqst; i++) {
1068 midQ[i] = server->ops->setup_request(ses, server, &rqst[i]);
1069 if (IS_ERR(midQ[i])) {
1070 revert_current_mid(server, i);
1071 for (j = 0; j < i; j++)
1072 cifs_delete_mid(midQ[j]);
1073 mutex_unlock(&server->srv_mutex);
1075 /* Update # of requests on wire to server */
1076 for (j = 0; j < num_rqst; j++)
1077 add_credits(server, &credits[j], optype);
1078 return PTR_ERR(midQ[i]);
1081 midQ[i]->mid_state = MID_REQUEST_SUBMITTED;
1082 midQ[i]->optype = optype;
1084 * Invoke callback for every part of the compound chain
1085 * to calculate credits properly. Wake up this thread only when
1086 * the last element is received.
1088 if (i < num_rqst - 1)
1089 midQ[i]->callback = cifs_compound_callback;
1091 midQ[i]->callback = cifs_compound_last_callback;
1093 cifs_in_send_inc(server);
1094 rc = smb_send_rqst(server, num_rqst, rqst, flags);
1095 cifs_in_send_dec(server);
1097 for (i = 0; i < num_rqst; i++)
1098 cifs_save_when_sent(midQ[i]);
1101 revert_current_mid(server, num_rqst);
1102 server->sequence_number -= 2;
1105 mutex_unlock(&server->srv_mutex);
1108 * If sending failed for some reason or it is an oplock break that we
1109 * will not receive a response to - return credits back
1111 if (rc < 0 || (flags & CIFS_NO_SRV_RSP)) {
1112 for (i = 0; i < num_rqst; i++)
1113 add_credits(server, &credits[i], optype);
1118 * At this point the request is passed to the network stack - we assume
1119 * that any credits taken from the server structure on the client have
1120 * been spent and we can't return them back. Once we receive responses
1121 * we will collect credits granted by the server in the mid callbacks
1122 * and add those credits to the server structure.
1126 * Compounding is never used during session establish.
1128 if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP))
1129 smb311_update_preauth_hash(ses, rqst[0].rq_iov,
1132 for (i = 0; i < num_rqst; i++) {
1133 rc = wait_for_response(server, midQ[i]);
1138 for (; i < num_rqst; i++) {
1139 cifs_server_dbg(VFS, "Cancelling wait for mid %llu cmd: %d\n",
1140 midQ[i]->mid, le16_to_cpu(midQ[i]->command));
1141 send_cancel(server, &rqst[i], midQ[i]);
1142 spin_lock(&GlobalMid_Lock);
1143 midQ[i]->mid_flags |= MID_WAIT_CANCELLED;
1144 if (midQ[i]->mid_state == MID_REQUEST_SUBMITTED) {
1145 midQ[i]->callback = cifs_cancelled_callback;
1146 cancelled_mid[i] = true;
1147 credits[i].value = 0;
1149 spin_unlock(&GlobalMid_Lock);
1153 for (i = 0; i < num_rqst; i++) {
1157 rc = cifs_sync_mid_result(midQ[i], server);
1159 /* mark this mid as cancelled to not free it below */
1160 cancelled_mid[i] = true;
1164 if (!midQ[i]->resp_buf ||
1165 midQ[i]->mid_state != MID_RESPONSE_RECEIVED) {
1167 cifs_dbg(FYI, "Bad MID state?\n");
1171 buf = (char *)midQ[i]->resp_buf;
1172 resp_iov[i].iov_base = buf;
1173 resp_iov[i].iov_len = midQ[i]->resp_buf_size +
1174 server->vals->header_preamble_size;
1176 if (midQ[i]->large_buf)
1177 resp_buf_type[i] = CIFS_LARGE_BUFFER;
1179 resp_buf_type[i] = CIFS_SMALL_BUFFER;
1181 rc = server->ops->check_receive(midQ[i], server,
1182 flags & CIFS_LOG_ERROR);
1184 /* mark it so buf will not be freed by cifs_delete_mid */
1185 if ((flags & CIFS_NO_RSP_BUF) == 0)
1186 midQ[i]->resp_buf = NULL;
1191 * Compounding is never used during session establish.
1193 if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP)) {
1195 .iov_base = resp_iov[0].iov_base,
1196 .iov_len = resp_iov[0].iov_len
1198 smb311_update_preauth_hash(ses, &iov, 1);
1203 * This will dequeue all mids. After this it is important that the
1204 * demultiplex_thread will not process any of these mids any futher.
1205 * This is prevented above by using a noop callback that will not
1206 * wake this thread except for the very last PDU.
1208 for (i = 0; i < num_rqst; i++) {
1209 if (!cancelled_mid[i])
1210 cifs_delete_mid(midQ[i]);
1217 cifs_send_recv(const unsigned int xid, struct cifs_ses *ses,
1218 struct smb_rqst *rqst, int *resp_buf_type, const int flags,
1219 struct kvec *resp_iov)
1221 return compound_send_recv(xid, ses, flags, 1, rqst, resp_buf_type,
1226 SendReceive2(const unsigned int xid, struct cifs_ses *ses,
1227 struct kvec *iov, int n_vec, int *resp_buf_type /* ret */,
1228 const int flags, struct kvec *resp_iov)
1230 struct smb_rqst rqst;
1231 struct kvec s_iov[CIFS_MAX_IOV_SIZE], *new_iov;
1234 if (n_vec + 1 > CIFS_MAX_IOV_SIZE) {
1235 new_iov = kmalloc_array(n_vec + 1, sizeof(struct kvec),
1238 /* otherwise cifs_send_recv below sets resp_buf_type */
1239 *resp_buf_type = CIFS_NO_BUFFER;
1245 /* 1st iov is a RFC1001 length followed by the rest of the packet */
1246 memcpy(new_iov + 1, iov, (sizeof(struct kvec) * n_vec));
1248 new_iov[0].iov_base = new_iov[1].iov_base;
1249 new_iov[0].iov_len = 4;
1250 new_iov[1].iov_base += 4;
1251 new_iov[1].iov_len -= 4;
1253 memset(&rqst, 0, sizeof(struct smb_rqst));
1254 rqst.rq_iov = new_iov;
1255 rqst.rq_nvec = n_vec + 1;
1257 rc = cifs_send_recv(xid, ses, &rqst, resp_buf_type, flags, resp_iov);
1258 if (n_vec + 1 > CIFS_MAX_IOV_SIZE)
1264 SendReceive(const unsigned int xid, struct cifs_ses *ses,
1265 struct smb_hdr *in_buf, struct smb_hdr *out_buf,
1266 int *pbytes_returned, const int flags)
1269 struct mid_q_entry *midQ;
1270 unsigned int len = be32_to_cpu(in_buf->smb_buf_length);
1271 struct kvec iov = { .iov_base = in_buf, .iov_len = len };
1272 struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 };
1273 struct cifs_credits credits = { .value = 1, .instance = 0 };
1274 struct TCP_Server_Info *server;
1277 cifs_dbg(VFS, "Null smb session\n");
1280 server = ses->server;
1281 if (server == NULL) {
1282 cifs_dbg(VFS, "Null tcp session\n");
1286 if (server->tcpStatus == CifsExiting)
1289 /* Ensure that we do not send more than 50 overlapping requests
1290 to the same server. We may make this configurable later or
1293 if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
1294 cifs_server_dbg(VFS, "Illegal length, greater than maximum frame, %d\n",
1299 rc = wait_for_free_request(server, flags, &credits.instance);
1303 /* make sure that we sign in the same order that we send on this socket
1304 and avoid races inside tcp sendmsg code that could cause corruption
1307 mutex_lock(&server->srv_mutex);
1309 rc = allocate_mid(ses, in_buf, &midQ);
1311 mutex_unlock(&server->srv_mutex);
1312 /* Update # of requests on wire to server */
1313 add_credits(server, &credits, 0);
1317 rc = cifs_sign_smb(in_buf, server, &midQ->sequence_number);
1319 mutex_unlock(&server->srv_mutex);
1323 midQ->mid_state = MID_REQUEST_SUBMITTED;
1325 cifs_in_send_inc(server);
1326 rc = smb_send(server, in_buf, len);
1327 cifs_in_send_dec(server);
1328 cifs_save_when_sent(midQ);
1331 server->sequence_number -= 2;
1333 mutex_unlock(&server->srv_mutex);
1338 rc = wait_for_response(server, midQ);
1340 send_cancel(server, &rqst, midQ);
1341 spin_lock(&GlobalMid_Lock);
1342 if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
1343 /* no longer considered to be "in-flight" */
1344 midQ->callback = DeleteMidQEntry;
1345 spin_unlock(&GlobalMid_Lock);
1346 add_credits(server, &credits, 0);
1349 spin_unlock(&GlobalMid_Lock);
1352 rc = cifs_sync_mid_result(midQ, server);
1354 add_credits(server, &credits, 0);
1358 if (!midQ->resp_buf || !out_buf ||
1359 midQ->mid_state != MID_RESPONSE_RECEIVED) {
1361 cifs_server_dbg(VFS, "Bad MID state?\n");
1365 *pbytes_returned = get_rfc1002_length(midQ->resp_buf);
1366 memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
1367 rc = cifs_check_receive(midQ, server, 0);
1369 cifs_delete_mid(midQ);
1370 add_credits(server, &credits, 0);
1375 /* We send a LOCKINGX_CANCEL_LOCK to cause the Windows
1376 blocking lock to return. */
1379 send_lock_cancel(const unsigned int xid, struct cifs_tcon *tcon,
1380 struct smb_hdr *in_buf,
1381 struct smb_hdr *out_buf)
1384 struct cifs_ses *ses = tcon->ses;
1385 LOCK_REQ *pSMB = (LOCK_REQ *)in_buf;
1387 /* We just modify the current in_buf to change
1388 the type of lock from LOCKING_ANDX_SHARED_LOCK
1389 or LOCKING_ANDX_EXCLUSIVE_LOCK to
1390 LOCKING_ANDX_CANCEL_LOCK. */
1392 pSMB->LockType = LOCKING_ANDX_CANCEL_LOCK|LOCKING_ANDX_LARGE_FILES;
1394 pSMB->hdr.Mid = get_next_mid(ses->server);
1396 return SendReceive(xid, ses, in_buf, out_buf,
1397 &bytes_returned, 0);
1401 SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
1402 struct smb_hdr *in_buf, struct smb_hdr *out_buf,
1403 int *pbytes_returned)
1407 struct mid_q_entry *midQ;
1408 struct cifs_ses *ses;
1409 unsigned int len = be32_to_cpu(in_buf->smb_buf_length);
1410 struct kvec iov = { .iov_base = in_buf, .iov_len = len };
1411 struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 };
1412 unsigned int instance;
1413 struct TCP_Server_Info *server;
1415 if (tcon == NULL || tcon->ses == NULL) {
1416 cifs_dbg(VFS, "Null smb session\n");
1420 server = ses->server;
1422 if (server == NULL) {
1423 cifs_dbg(VFS, "Null tcp session\n");
1427 if (server->tcpStatus == CifsExiting)
1430 /* Ensure that we do not send more than 50 overlapping requests
1431 to the same server. We may make this configurable later or
1434 if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
1435 cifs_tcon_dbg(VFS, "Illegal length, greater than maximum frame, %d\n",
1440 rc = wait_for_free_request(server, CIFS_BLOCKING_OP, &instance);
1444 /* make sure that we sign in the same order that we send on this socket
1445 and avoid races inside tcp sendmsg code that could cause corruption
1448 mutex_lock(&server->srv_mutex);
1450 rc = allocate_mid(ses, in_buf, &midQ);
1452 mutex_unlock(&server->srv_mutex);
1456 rc = cifs_sign_smb(in_buf, server, &midQ->sequence_number);
1458 cifs_delete_mid(midQ);
1459 mutex_unlock(&server->srv_mutex);
1463 midQ->mid_state = MID_REQUEST_SUBMITTED;
1464 cifs_in_send_inc(server);
1465 rc = smb_send(server, in_buf, len);
1466 cifs_in_send_dec(server);
1467 cifs_save_when_sent(midQ);
1470 server->sequence_number -= 2;
1472 mutex_unlock(&server->srv_mutex);
1475 cifs_delete_mid(midQ);
1479 /* Wait for a reply - allow signals to interrupt. */
1480 rc = wait_event_interruptible(server->response_q,
1481 (!(midQ->mid_state == MID_REQUEST_SUBMITTED)) ||
1482 ((server->tcpStatus != CifsGood) &&
1483 (server->tcpStatus != CifsNew)));
1485 /* Were we interrupted by a signal ? */
1486 if ((rc == -ERESTARTSYS) &&
1487 (midQ->mid_state == MID_REQUEST_SUBMITTED) &&
1488 ((server->tcpStatus == CifsGood) ||
1489 (server->tcpStatus == CifsNew))) {
1491 if (in_buf->Command == SMB_COM_TRANSACTION2) {
1492 /* POSIX lock. We send a NT_CANCEL SMB to cause the
1493 blocking lock to return. */
1494 rc = send_cancel(server, &rqst, midQ);
1496 cifs_delete_mid(midQ);
1500 /* Windows lock. We send a LOCKINGX_CANCEL_LOCK
1501 to cause the blocking lock to return. */
1503 rc = send_lock_cancel(xid, tcon, in_buf, out_buf);
1505 /* If we get -ENOLCK back the lock may have
1506 already been removed. Don't exit in this case. */
1507 if (rc && rc != -ENOLCK) {
1508 cifs_delete_mid(midQ);
1513 rc = wait_for_response(server, midQ);
1515 send_cancel(server, &rqst, midQ);
1516 spin_lock(&GlobalMid_Lock);
1517 if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
1518 /* no longer considered to be "in-flight" */
1519 midQ->callback = DeleteMidQEntry;
1520 spin_unlock(&GlobalMid_Lock);
1523 spin_unlock(&GlobalMid_Lock);
1526 /* We got the response - restart system call. */
1530 rc = cifs_sync_mid_result(midQ, server);
1534 /* rcvd frame is ok */
1535 if (out_buf == NULL || midQ->mid_state != MID_RESPONSE_RECEIVED) {
1537 cifs_tcon_dbg(VFS, "Bad MID state?\n");
1541 *pbytes_returned = get_rfc1002_length(midQ->resp_buf);
1542 memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
1543 rc = cifs_check_receive(midQ, server, 0);
1545 cifs_delete_mid(midQ);
1546 if (rstart && rc == -EACCES)
1547 return -ERESTARTSYS;